PLATE XXVI. 
(The cost of this plate has been defrayed by the Carnegie ‘Trust for the Universities 
of Scotland.) 
Fic. 
1. Mematoptychius Greenocki, Traquair ; natural size. From the Lower Carboniferous 
(Calciferous Sandstone Series) at Wardie, near Edinburgh. One of the type 
specimens, in the Collection of the Author. 
2. Caudal portion of another specimen, from the Dunnet Shale of Straiton, Midlothian ; 
natural size. In the Royal Scottish Museum, Edinburgh. 
3. A nearly entire cranial buckler of the same species seen from the internal surface ; 
natural size; from the same horizon and locality as no. 2. /f, frontals; pa., 
parietals ; sg., squamosals ; ¢., superethmoidal ; s. ¢., sensory canal. 
4. Detached preopercular plate of the same species ; natural size. From the roof-shale 
of the *f South Parrot” coal-seam, Niddrie, Midlothian (Upper Limestone Group). 
In the Royal Scottish Museum, Edinburgh. 
5. Maxillary bone of the same species, from the same horizon and locality as no. 4. 
‘The posterior expanded portion is seen only in impression, but the bone 1s 
preserved along the dentary margin, where it displays, numerous Janmiary teeth. 
6. Dentary element of the mandible of the same species, seen from the outside and 
magnified by one half. ‘he sculpture of the external surface and the dentition are 
well displayed. From the Calciferous Sandstone Series, Pitcorthy, Fifeshire. In 
the Royal Scottish Museum, Edinburgh. 
7. Maxillary laniary tooth of the same species, seen from the inner surface and magimfied 
six diameters. ‘The enamel-cap of the apex is well shown, and, a piece of the base 
of the tooth having been splintered off, the wide pulp cavity of this portion of the 
tooth, filled with calcareous spar, is displayed. From Wardie. 
8. A fragment, showing the proximal part of the left pectoral fin of the same species ; 
natural size. From Wardie. In the Collection of the Author. 
9. Flank-scale of the same species, showing the external sculptured surface and the 
articular process of the upper margin; magnified three diameters. From Wardie. 
10. Inner surface of a similar scale, magnified three diameters. From Wardie. 
11. External sculptured surfaces of a group of four dorsal scales, also magnified three 
diameters. From Wardie. 
